| 摘要 |
PURPOSE:To reduce the internal stress of a lower electrode film, and to minimize an impurity in the lower electrode film by using structure consisting or a tunnel barrier layer formed onto a first superconductor layer and a second superconductor layer shaped onto the tunnel barrier layer. CONSTITUTION:A substrate upper layer 2 is formed onto a substrate lower layer 1 consisting of an Si single crystal through a resistance heating evaporation method. The substrate upper layer 2 has a stepped section, but an insulating film 3 for coating is deposited onto the layer 2. A lower electrode 4 and a tunnel barrier layer 5 are shaped by machining through a reactive ion etching method. An upper electrode 6 is formed by machining through the reactive ion etching method again, and an Si film is deposited through the resistance heating evaporation method and an inter-layer insulating film 7 is shaped by machining through a lift-off method. Lastly, a Pb-In alloy film is deposited through the resistance heating evaporation method, and used as a superconducting wiring layer 8. Accordingly, the adverse effect of internal stress can be avoided in the same manner as conventional devices while the problem of a superconducting contact and the problem, etc., of the diffusion of an impurity existing on the interface of a thin-film can be solved. |
